Category Archives: Theory of Computation & Automata

Prerequisite – Finite Automata Introduction Problem – Draw deterministic finite automata (DFA) of the language containing the set of all strings over {a, b} in… Read More
Automata is a machine that can accept the Strings of a Language L over an input alphabet . So far we are familiar with the… Read More
To understand better the halting problem, we must know Decidability, Undecidability and Turing machine, decision problems and also a theory named as Computability theory and… Read More
Prerequisite – Pushdown automata, Pushdown automata acceptance by final state The language L = {0i1j2k | i==j or j==k ; i , j , k… Read More
Prerequisite – Turing Machine, Turing machine for subtraction | Set 1 A number is represented in binary format in different finite automatas like 5 is… Read More
Prerequisite – Pushdown automata, NPDA for accepting the language L = {ambnc(m+n) | m,n ≥ 1} PDA plays a very important role in task of… Read More
Prerequisite – Turing Machine In a given language, L = {aibjck | i*j = k; i, j, k ≥ 1}, where every string of ‘a’, ‘b’… Read More
Prerequisite – Pushdown automata, Pushdown automata acceptance by final state PDA plays a very important role in task of compiler designing. That is why there… Read More
Computable Problems – You are familiar with many problems (or functions) that are computable (or decidable), meaning there exists some algorithm that computes an answer… Read More
Prerequisite – Pumping Lemma, How to identify if a language is regular or not We typically face questions to identify which of the given languages… Read More
Prerequisite – Regular Expressions, Regular Grammar and Regular Languages, Pumping Lemma There is a well established theorem to identify if a language is regular or not,… Read More
Prerequisite – Vertex Cover Problem, NP-Completeness Problem – Given a graph G(V, E) and a positive integer k, the problem is to find whether there… Read More
Prerequisite – Pushdown automata, Pushdown automata acceptance by final state  Problem – Design a non deterministic PDA for accepting the language L = {| m… Read More
Prerequisite – Pushdown automata, Pushdown automata acceptance by final state Problem – Design a non deterministic PDA for accepting the language L = {a2mb3m |… Read More
Prerequisite – Finite automata, L-graphs and what they represent L-graphs can generate context sensitive languages, but it’s much harder to program a context sensitive language… Read More